Question

Menthol is a crystalline substance with a peppermint taste and odor. When 0.990 g of menthol...

Menthol is a crystalline substance with a peppermint taste and odor. When 0.990 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 5.28 °C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of menthol in g/mol.

Science   Chemistry   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

Dear Friend your answer is

  1. Step 1: Calculate the freezing point depression of the solution.

    Tf = (Freezing point of pure solvent) - (Freezing point of solution)
    (20.1 oC) - (5.28 oC) = 14.73 oC
  2. Step 2 : Calculate the molal concentration of the solution using the freezing point depression.

    Tf = (Kf) (m)
    m = (14.73 oC) / (6.5 oC/molal)
    m = 2.2661 molal
  3. Step 3: Calculate the molar mass of the unknown using the molal concentration.

    m = 2.2661 molal = 2.2661 mol menthol / kg cyclohexane

    moles menthol = (2.2661 mol menthol / kg cyclohexane) (0.099 kg cyclohexane) = 2.2889 X 10-3 mol menthol

    molar mass of menthol = (0.99 g menthol) / (2.2889 X 10-3 mol menthol)

    molar mass of menthol = 432.5221 g/mol

Thank you, all the best.

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Menthol is a crystalline substance with a peppermint taste and odor. When 0.960 g of menthol...
Menthol is a crystalline substance with a peppermint taste and odor. When 0.960 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 5.12 °C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of menthol.
Menthol is a crystalline substance with a peppermint taste and odor. When 0.606 g of menthol...
Menthol is a crystalline substance with a peppermint taste and odor. When 0.606 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 3.23 °C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of menthol. Solvent Formula Kf value* (°C/m) Normal freezing point (°C) Kb value (°C/m) Normal boiling point (°C) water H2O 1.86 0.00 0.512 100.00 benzene C6H6 5.12 5.49 2.53 80.1...
Quinine is a natural product extracted from the bark of the cinchona tree, which is native...
Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 2.03 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 5.20 °C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of quinine.
Quinine is a natural product extracted from the bark of the cinchona tree, which is native...
Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 1.86 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 4.77 °C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of quinine.
Vitamin K is involved in normal blood clotting. When 1.98 g of vitamin K is dissolved...
Vitamin K is involved in normal blood clotting. When 1.98 g of vitamin K is dissolved in 25.0 g of camphor, the freezing point of the solution is lowered by 6.63 °C. The freezing point and Kf constant for camphor can be found here. Calculate the molar mass of vitamin K.
Quinine is a natural product extracted from the bark of the cinchona tree, which is native...
Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 2.94 g 2.94 g of quinine is dissolved in 25.0 g 25.0 g of cyclohexane, the freezing point of the solution is lowered by 7.54 ∘ C. 7.54 ∘C. Look up the freezing point and K f Kf constant for cyclohexane in the Colligative Constants table. Calculate the molar mass of quinine.
Quinine is a natural product extracted from the bark of the cinchona tree, which is native...
Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 0.783 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 2.01 ∘ C. Look up the freezing point and K f constant for cyclohexane in the Colligative Constants table. Calculate the molar mass of quinine.
The freezing point of biphenyl (molar mass 154g/mole) is 71.0 degrees. When 1.240 g of benzophenone...
The freezing point of biphenyl (molar mass 154g/mole) is 71.0 degrees. When 1.240 g of benzophenone (molar mass 182 g/mole) is added to 9.52 g of biphenyl the solution is found to freeze at 14.3 degrees Celsius. Calculate the freezing point depression constant, Kf, for biphenyl.
A 0.194 g sample of a nonvolatile solid solute dissolves in 9.82 g of cyclohexane.? the...
A 0.194 g sample of a nonvolatile solid solute dissolves in 9.82 g of cyclohexane.? the change in the freezing point is 2.94 C. Kf= 20 a)- What is the molality of the solute in the solution? b) Calculate the molar mass (sig figs) c) The same mass of solute is disolved in 9.82 g of t-butanol instead of cyclohexane. WHat is the freezing point? (Kf=9.1) (Freezing Point= 25.5 C)
Consider that you prepared a solution by mixing 0.14 g organic solute with 7.81 g of...
Consider that you prepared a solution by mixing 0.14 g organic solute with 7.81 g of cyclohexane. If you measured that the freezing point of the solution was 4.86 oC, what is the molar mass of the organic solute? Cyclohexane has a freezing point of 6.55oC and Kf= -20.2 °C/m. Express your answer in units of g/mol to to three significant figures.
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT